Distinguishing between Big Preface and Small Preface in Mao Zedong's Poetry

Preface to Mao Shi, an ancient theory of Chinese poetry. The author says that Xia Zi, a disciple of Kong Qiu, wrote the preface for The Book of Songs, and Wei Hong, a Han Chinese, wrote the preface for The Book of Songs, which can be divided into big preface and small preface. The grand preface refers to the general preface of all the Books of Songs written by the author after explaining Guanju, and the minor preface refers to the preface of each of the 305 Books of Songs. Generally speaking, Preface to Mao Poetry refers to a grand preface. The author is controversial.